Stuck Plenum

[Denis]

Am trying to pull the plenum to install a new set of injectors, followed the steps outlined in the forum but it will not budge. It appears that the former owner used some kind of gasket sealer on both sides of the plenum gasket and the thing is glued together to the extent that I am afraid to pry on it any harder for fear of breaking something.

Am looking for suggestions. A thick plenum gasket was used and the sealer that is there by the edge of the gasket is quite hard.

[LGAFF]

1)double check all the bolts are off

2)block of wood and tap it with a hammer or rubber mallet

[GOLDCYLON]

1)double check all the bolts are off

2)block of wood and tap it with a hammer or rubber mallet

What Lee said

[Dynomite]

1)double check all the bolts are off

2)block of wood and tap it with a hammer or rubber mallet

I am not so sure I understand the "block of wood" trick :confused:

Block of wood under what, wedged where?

Hit by hammer or rubber mallet are two different animals completely (am assuming you hit the block of wood) :p

I would have to look but I think you can get a wooden wedge between the AC compressor and air horn to apply upward pressure on front of plenum.....just an idea.

I would be vary careful in trying to wedge a flat screw driver between Plenum runners and Injector Housing where gasket is located no matter how thick as you will/might damage/scar the aluminum mating surfaces.

I am assuming you drained some coolant down below the Injector Housing level ;)

[LGAFF]

You put the block against the plenum(edge) and hit it with the hammer...loosens it up

[Dynomite]

You put the block against the plenum(edge) and hit it with the hammer...loosens it up

That makes sense.....and might also apply pressure upward with a wedge between AC and Air horn when you tap Plenum with block of wood and hammer :handshak:

I run into this on Cam Covers but as you know there are two recessed grooves in each cam cover to slip a flat screw driver to carefully apply separation pressure :thumbsup:

[mike100]

You put the block against the plenum(edge) and hit it with the hammer...loosens it up

yep, poor man's dead blow hammer.

I have been know to turn a regular ball peen around and hit the part with the wooden end.

[LGAFF]

I had one really stuck, should not admit this but I had the TB off, stuck a steel jack handle in the TB opening and lifted it up....

[Denis]

Many thanks, I appreciate the suggestions. I tried a gentle pry between the ac and the air horn but I chickened out when nothing moved.

I keep checking to see if all the bolts are out but unfortunately they all are.

Tomarow I will give the block of wood and hammer a try and see what happens.

Just can not believe the guy did what he did!!

[Schrade]

Welcome onto the boards there.

Why are you changing injectors? Did the static FP / pressure leakdown time fail?

[Denis]

Am changing the injectors because it appears that they are sticking closed.

Previous owner tried to fix the problem and changed the coil packs, wires and plugs.

The car only has 36000 miles on it and is a '90, serial 1234. It sat a lot and with the 10% alcohol in the California gas I suspect moisture in the fuel is killing the injectors. The previous owner had the car 10+ years and drove it less than 10K miles.

I took it for a 500 mile round trip recently. Drove the car about 250 miles in about 4.5 hours and it ran fine. I let it sit about 45 minutes, when I got back in the car and started it only had about 6 cylinders working. This issue has repeated a number of times since. The fix is to take it out on the road and run it wide open to the red line and then all is fine.

I have a 65 Olds Cutlass w/SBC, FAST XFI injection and on that car the injectors stuck open due to the moisture in fuel issue. Ended up having to replace all of the injectors with the new style stainless ones.

[RHanselman]

I am not so sure I understand the "block of wood" trick :confused:

Your life has been too sheltered...:)

[Dynomite]

Your life has been too sheltered...:)

You might be surprised how many ways I can use a block of wood :D

Hitting a small block of wood with a hammer used to cushion/distribute the blow to the plenum is one way.....
Using a 4x4 about 3 ft long and moving it (impacting) the plenum is another way.
Actually using a small block of wood to cushion the blow on the plenum of the 4x4x 3 ft long block having momentum works purty goot also ;)

I use the 4x4x3 ft block of wood on Rotors for example that refuse to release from the wheel hub.

A small hammer does not have much momentum....a 4x4x3ft block of wood has lots of momentum.

[Franke]

Hey Dyno, what a mental image you just posed. :) I was thinking what a dealer customer might say if they saw a tech using a block of wood 4x4x3' to dislodge their rotors. Of course your method does work but it is a bit unconventional to the untrained eye.

[Denis]

Got it apart. Gentle prying between the alternator and air horn and a block of wood and hammer. Did not take a lot and I was pleasantly suprised.

Found three different primary injectors and three different secondary injectors in the engine.... Obviously this is not the first time that there were problems with the injectors. I am suprised, I use flow matched injectors on the Olds and there is no way that the ones on the ZR1 were matched. On the primary set some are actually longer top to bottom than the others.

Now am going to have fun getting all the gasket material off. Looks like straight alcohol cuts the sealer. Got rags down all the intake ports. And am going to leave the injectors in place untill everything is clean.

[Schrade]

Sounds great...

But the part about injectors sticking open sounds unusual. I thought when they powered down, that the pintle is closed? Wouldn't only dirt hold them stuck open?

Or do the pintle springs break, and allow them to hang open???

[Denis]

I do not know except that I sent the failed injector to Jon at the Fuel Injector Connection and was informed that it was "stuck", and that they could not repair it. It was a Bosch injector, less than 2 years old. When I had a second one fail the same way I got the new style EV-6 LS type injectors which are designed to work with ethanol and have not had any problems since.

I am using a SX pump and SX inline 10 micron filter so dirt should not have been an issue. The injector screens looked clean when I inspected them.

[Schrade]

Your life has been too sheltered...:)You might be surprised how many ways I can use a block of wood :D

Hitting a small block of wood with a hammer used to cushion/distribute the blow to the plenum is one way.....
Using a 4x4 about 3 ft long and moving it (impacting) the plenum is another way.
Actually using a small block of wood to cushion the blow on the plenum of the 4x4x 3 ft long block having momentum works purty goot also ;)

I use the 4x4x3 ft block of wood on Rotors for example that refuse to release from the wheel hub.

A small hammer does not have much momentum....a 4x4x3ft block of wood has lots of momentum.Exactly.


>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

He said "trick", which defines something SPECIFIC, that I don't know of either.

And I do know lots of other stuff - enough to put down the $$, and sit across from ANYone at a table, who's not so 'sheltered', and do some field-specific, objective testing, in any and every field, their's included...

Thread jam on bolts, and arrogance are alike - my pet peeves ;)